The present invention relates to heat transfer mechanisms; for example, to heat transfer mechanisms and cooling assemblies for removing heat generated by an electronic circuit module. More particularly, this invention relates to a cooling apparatus for cooling a heat generating component of an electronic module employing an airflow cooled heat sink structure.
The efficient extraction of heat from electronic circuit modules for very large scale integrated circuit packages has presented a significant limitation on the design and use of such electronic modules. The power consumed in the integrated circuits generates heat which must in turn be removed from the package. Lacking an efficient heat transfer mechanism, the speed, reliability and power capabilities of the electronic circuit modules are limited. As the density of circuitry within very large scale integrated circuit chips has increased, the need for improved heat extraction has become even more acute since more densely packed chips tend to have a higher need for heat dissipation per unit area. It is also known that runaway thermal conditions and excessive heat generated by chips is a leading cause of failure of chip devices. Furthermore it is anticipated that demand for heat removal from these devices will continue to increase indefinitely. Accordingly, it is seen that there is a significant need to continue to further improve upon cooling mechanisms for electronic devices, and in particular, to further improve upon air cooling capability for such devices.
The shortcomings of the prior approaches are overcome, and additional advantages are provided, by the present invention which in one aspect comprises a cooling assembly for facilitating heat transfer from an electronic module. Moreover, it should be understood that a cooling assembly in accordance with the present invention is not limited to cooling electronic modules, but rather, has many applications such as, for example, cooling heat generating mechanical components. For simplicity, the following discussion of a cooling assembly in accordance with an aspect of the present invention is focused on cooling electronic modules, with the understanding that it may be employed with other applications as well.
In one embodiment, a cooling apparatus in accordance with an aspect of the present invention includes a heat sink structure and an airflow tube assembly. The heat sink structure has a first surface for coupling to one or more heat generating components, and a second surface with at least one air-cooled fin extending therefrom. The airflow tube assembly has at least one airflow tube, with the at least one airflow tube being sized to at least partially receive the at least one fin of the heat sink structure. An annular airflow can be established between the at least one airflow tube and the at least one fin of the heat sink structure, thereby enhancing heat transfer from the heat sink structure to the airflow and cooling of the heat generating component.
In another aspect, an electronic assembly is provided which includes an electronic module comprising a heat generating component, and a cooling apparatus coupled to a surface of the electronic module for removing heat generated by the heat generating component. The cooling apparatus includes a heat sink structure and an airflow tube assembly. The heat sink structure has a first surface coupled to the heat generating component and a second surface with at least one fin extending therefrom. The airflow tube assembly has at least one airflow tube, with the at least one airflow tube being sized to at least partially receive the at least one fin of the heat sink structure. An annular airflow can be established between the at least one airflow tube and the at least one fin of the heat sink structure to enhance heat transfer from the heat sink structure to air and cooling of the heat generating component.
In a further aspect, a method of fabricating a cooling apparatus for a heat generating component is provided. The method includes: providing a heat sink structure having a first surface for coupling to the heat generating component and a second surface with at least one fin extending therefrom; and providing an airflow tube assembly having at least one airflow tube, the at least one airflow tube being sized to at least partially receive the at least one fin of the heat sink structure, wherein an annular airflow can be established between the at least one airflow tube and the at least one fin of the heat sink structure, thereby enhancing heat transfer from the heat sink structure to air and cooling of the heat generating component.
Advantageously, provided herein is a fin heat sink structure and airflow tube assembly which employ annular airflows to improve thermal performance of the cooling apparatus; that is, to provide lower temperatures at a given heat load or more heat removal at a given temperature by applying more uniform convective heat transfer on the fins, such as long, pin-type fins. In one embodiment, a uniform parallel annular airflow can be provided along the surface of the fins with a high heat transfer coefficient along the entire length of the fin by defining a small annular gap around each fin, for example, 10 mils or less. In addition, the benefit of a high heat transfer coefficient on the heat sink base due to the impinging airflow is retained.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.